The invention is generally directed to a printing apparatus and in particular to a printing apparatus which has a light source and a liquid crystal, PLZT, electrochromic, or similar shutter window (microshutter) device which causes the transmission and interception of light to effect the printing of letters and pictures.
The rapid growth in the use of personal computers and word processors in business offices as well as homes has developed a need for a small output device or printer which maintains a high degree of resolution. Apparatus which use a photo-sensitive body for printing generally use the electro-static latent image on a cylindrical drum to print. Various devices, such as a corona discharge station, developing station, transfer station, and electricity removal station are radially disposed around the drum. In addition, a printing device with a plurality of shutter windows (microshutter) is also required on the drum. If a panel having shutter windows (microshutter) or a printing device containing such a panel is placed on the drum, a large diameter drum is required to permit the radial arrangement of the various other devices around the drum. This necessarily results in a large printing apparatus. Accordingly, there is a need for a printing apparatus which includes a small diameter photosensitive drum, a limited number of moving parts and provides accurate printing.